Electrical annunciator-drop



(No Model.)

M HYNES ELECTRICAL ANNUNGIATOR DROP.

No. 425,078. PatehtedApr. s 1890.

' INVENTOR.

ATTORNEY.

gamma? 7fiM/ UNITED STATES PATENT ()FFICE.

MARTIN I-IYNES, OF BOSTON, MASSACHUSETTS.

ELECTRICAL ANNUNClATOR-DROP.

SPECIFICATION forming part of Letters Patent No. 425,078, dated April 8, 1890.

Application filed December 14, 1882. Serial No. 79,255. (No model.)

To aZZ whom it may concern.-

Be it known that I, MARTIN HYNES, of the city of Boston, county of Suffolk, and State of Massachusetts, have invented certain new and useful Improvements in Electrical Annunciator-Drops for Telephonic Signals; and

I do hereby declare that the following is afull and correct description of the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon which form a part of this specification.

Similar letters of reference are used to indicate like parts in all the drawings accompanying this specification. p

The object of my invention is to provide an electrical annunciator-drop particularly adapted for use in the central office of a telephonic exchange.

Figure 1 is a side view of my invention. Fig. 2 is a top view of the same. Fig. 3 is a front end view with the shutter-drop down, and Fig. 4 is a rear end view.

A is the base on which my annunciator rests, and B is the base-bar of the annunciator.

C is the shutter-drop provided with the metallic pin a, which is firmly soldered into the shutter-drop.

D is the adj usting-post on the front end of the annunciator, which is provided near its upper end with a circular slot at, through which the armature E passes. The post D is also provided with the adj Listing-screws b and d, which operate through its upper and bent portion.

The adjusting-screw 6, near the lower portion of the post D, is used for adjusting the shutter-drop O in a perpendicular position or at any desired angle.

The armature E is provided with the spring F, which is sc"ewed to the upper side of the armature.

G is a Y-shaped post at the rear end of the base-bar B, to which the rear end of the armature E is pivoted.

The spools H and H form the coils of the electro-magnet.

The binding-posts I andl are connected, respectively, with the base-bar B and the 10- cal-battery spring K.

The front end of the armature E is notched on its upper side at g, and with this engages the shutter-drop 0 when it is in an uprightposition.

The object of the adj llStlDg-SCYBWS b and d is obvioust0 regulate the armature E in its relation to the shutterdrop 0 and to the electro-magnet. By means of these adjusting screws the armature can be adapted to the electric currents as received from longer or shorter lines.

When a subscriber signals the central office of the telephonic exchange, the circuit through the annuuciator is closed. This causes the armature to vibrate, and thus releases the shutter-drop, which immediately falls down. In falling down the metallic pin 0 of the shutterdrop comes in contact with the local-battery spring K, which causes the bell to ring, and thus gives notice to the central office that a subscriber has called, and the number on the now-exposed face of the shutter-drop indicates the source of the call.

Having now fully described my invention, what I claim, and desire to secure by Letters Patent, is-

The armature E, provided with the spring F and the shutter-drop O, in combination with the post D, provided with the adj listing-screw e, to regulate the position of the shutter-drop O, the adjusting-screws b and d, the post G, and the electro-magnet H H, substantially as shown and described, and for the purposes herein set forth. 7 a

In testimony that I claim the foregoing I have hereunto set my hand this 9th day of December, 1882.

MARTIN HYNES. Witnesses:

J. M00. PERKINS, SAMUEL W. MCDANIEL. 

